int blinkled = 0;        // The current LED state. 
char packetBuffer[70];   // character array to hold outgoing data packets
IPAddress remote_ip(192,168,0,101);   // The PC running LabVIEW
unsigned int remote_port = 61558;     // The UDP port that LabVIEW is watching

int WHITELED = 2;  // Connection for LED

// Configure "activity" LED as output
void initBlinkingLED(){
  pinMode(WHITELED, OUTPUT);
}

void initSDCard(){
    if (!SD.begin(4)) {
        sdStatus = "SD card failed";
        FileOK = false;
    } else {
        sdStatus = "SD card good";
        FileOK = true;
    }
}
/**************************************************************************
    Blink, loop activity light 
 **************************************************************************/
void blinkTheLED() {
    if (blinkled){
        digitalWrite(WHITELED, LOW);
    } else {
        digitalWrite(WHITELED, HIGH);
    }
    blinkled = abs(blinkled-1); // 1-1=0, abs(0)=0 ; 0-1=-1, abs(-1)=1 (toggle between 0 and 1).
}

/**************************************************************************
    Convert IPAddress datatype to a human-readable string
 **************************************************************************/
String converIPtoString(IPAddress ip){
   long longIP = (long)ip;
   String firstOctet  = String(longIP & 0x000000FF);
   String secondOctet = String((longIP & 0x0000FF00)>>8);
   String thirdOctet  = String((longIP & 0x00FF0000)>>16);
   String fourthOctet = String((longIP & 0xFF000000)>>24);
   
   return firstOctet+"."+secondOctet+"."+thirdOctet+"."+fourthOctet;
}

/**************************************************************************
    Convert output string to charcter buffer and transmit it to LabVIEW
 **************************************************************************/
void sendOutputPacket(String output){
    int i = 0;
    memset(packetBuffer, 0, 99);
    while ((int)output[i] != 0){
        packetBuffer[i] = output[i];
        i = i + 1;
    }
    // send the output via UDP
    Udp.beginPacket(remote_ip, remote_port);
    Udp.write(packetBuffer);
    Udp.endPacket();
}